Transcript Cell Notes
Nerve cells Muscle cells Fat cells Bone cell Epithelial cells Cytology - the study of the structure, function and diseases of cells Cell Parts - Chart 3.1 pg 56, diagram pg 49 Fig 3.2 Plasma Membrane -Selectively permeable membrane -Phospholipid bilayer/Fluid Mosaic model Diffusion Simple Diffusion- molecules and ions pass from areas of higher concentration to areas of lower concentrations. http://www.indiana.edu/~phys215/lecture/lecnotes/diff.html Facilitated diffusion- requires a carrier molecule for diffusion to take place. Active Transport -Sodium-Potassium Pump - against concentration gradient Osmosis - water diffuses from higher concentration to lower concentration *selectively permeable - allows water to flow freely but not glucose Tonicity - the osmotic pressure of a solution -cells swell and shrink with changes in tonicity A. Isotonic - equilibrium of water and solute B. Hypertonic - higher concentration of solute outside the cell C. Hypotonic - lesser concentration of solute outside the cell *Visual of Hypertonic, Hypotonic and Isotonic http://www.connect.ab.ca/~lburns/students_tenunit2note.ht ml Filtration - when molecules are forced through membranes (hydrostatic pressure). Vessicular Transport Endocytosis - when particles enter into the cell by means of a vesicle. 1. Pinocytosis : liquids enter into the cell in a vesicle 2. Phagocytosis : solids enter into the cell in a vesicle Vessicular Transport Exocytosis : particles and liquids exit out of the cell Cytoplasm - the clear liquid that is essentially the site of metabolic rxns Organelles Centrosome - two hollow cylinderical centrioles Centriole - active in separating chromosomes in cell division Cilia - small hairlike structures on the surface of the cell membrane, wavelike motion. Flagella - longer projection on the surface of the cell, undulating wavelike motion. Ribosomes - composed of protein and RNA, sites of protein synthesis Rough Endoplasmic Reticulum - a network of tubes that transport materials, contain ribosomes on their surface Smooth Endoplasmic Reticulum - transports materials, synthesize lipids Golgi Apparatus - flat sacs that package, process and transport proteins Lysosomes - digest worn out cellular parts or toxins Peroxisomes – sac containing enzymes that help detoxify (contain enzymes peroxidase and catalase) Mitochondria - release and transform energy into useable forms Nucleus - control center of cell, contains DNA Nuclear membrane - a porous double layer membrane that surrounds the nucleus Nucleolus - a dense body composed of RNA and protein, forms ribosomes Chromatin - loosely coiled chromosomes made of protein and DNA DNA -> mRNA-> tRNA -> protein Replication - copy of DNA Transcription - DNA splits, mRNA read DNA, enters cytoplasm, binds to ribosome Translation - mRNA is translated into DNA code by tRNA and amino acids are left TO: endoplasmic reticulum nucleus protein on its way! DNA RNA TO: vesicle TO: TO: vesicle TO: ribosomes finished protein protein Golgi apparatus Making Proteins Cell Cycle *responsible for the growth of an infant, as well as the repair and replacement of cells. Interphase - grow, replicate, and prepare for division Prophase - chromosomes become visible, nuclear envelop disappears, spindle fibers appear and centrosomes move to opposite poles. Metaphase - chromosomes line up at midline and spindle fibers attach to the centromere. Anaphase - sister chromatids separate and move to poles, spindle fibers contract or shorten pulling them apart. Telophase - chromosomes condense and nuclear envelop appears Cytokinesis - division of cytoplasm Mitosis Website: http://www.biology.arizona.edu/cell_bio/tutorials/cell_cycle/cells3.html Cell Cycle plays a role in : 1. Aging Geriatrics - the branch of medical science that deals with diseases and problems specific to old people 2. Cancer Oncology - the branch of medicine that deals with tumors, including study of their development, diagnosis, treatment, and prevention. 3. Tumor or neoplasm benign - noncancerous growth malignant - cancerous growth 4. Metastasis - transfer of a disease-producing agency (as cancer cells or bacteria) from an original site of disease to another part of the body metastasis in the lung usually occurs by way of the blood stream metastases of breast cancer to bone *Read Box 4-1 on p115 and know the difference between hyperplasia and anaplasia, neoplasm, hypertrophy, and atrophy. Cancer - a change in your cell structure that inactivates cellular activities Apoptosis - a programmed cell death signaled by the nuclei in normally functioning cells when they age, or become diseased. *cancerous cells are unable to experience natural cell death Types of Cancer 1. Carcinomas - an invasive malignant tumor derived from epithelial tissue and tends to metastasize to other areas. 2. Sarcomas - a malignant tumor arising from connective tissue 3. Leukemia - cancer of the blood forming tissues Causes of Cancer 1. Mutagen - DNA mutates or gene is altered 2. Carcinogen - chemicals/toxins, radiation etc Genes involved in Cancer •tumor suppressor genes •proto-oncogenes - normal cellular genes involved in regulating and maintaining cell division •Oncogenes - genes that potentially induce tumor transformation, they replace normal genes Treatments *Surgery - removal of mass from tissue *Chemotherapy - use of drugs or chem agents to destroy malignant cells/tissues *Radiation therapy - exposure to radiation (X-rays) to treat disease *Immunotherapy - induce, enhance or suppress immune response